Bending ball arbor



Oct. 19, 1948. F, M CHECK, 5R 1 2,451,717

BENDING BALL ARBOR Filed June 21, 1946 2 Sheets-Sheet 1 INVENTOR. FRANK NLCHECK SR.

ATTO R NEYS Oct. 19, 1948. F, M CHECK, SR 2,451,717

BENDING BALL ARBOR Filed June 21, 1946 2 sheets-sheet 2 FIG. 6..

INVENTOR. FRANK M. cHEcK,sR,

Patented Oct. 19, 1948 UNITED STATES PATENT# OFFICE Frank lVI. Check, Sr., Stratford, Conn.

Application June 2,1, 1946, Serial No. 678,430

This invention relates to a bending ball arbor, and more particularly to such an arbor adapted to be utilized when bending tubular material.

A primary object of this invention is the provision of an improved bending ball arbor, or articulated mandrel, adapted to be positioned interiorly of the tubing during the process of bending to insure a relatively smooth and a-ccurate bend in the tube. n

Ajfurther object of the invention is the provisionof such an arbor which may be advantageously utilized in the formation of bends in tubing of relatively small radius.

A further and very important object of the invention is the provision of such a device characterized by links securing the several balls in related assembly, the'links beingheld in position by pins which do not extend exteriorly of the balls',`thus obviating the possibility of accidental displacement of a pin, or pins, during the bending operation, and consequent spoilage of the tubing and breakage of the bending apparatus.

Afstill further. object of the invention is the provision of such a device which is sturdy and durable in construction, reliable and eiiicient in operation, and relatively simple and inexpensive to manufacture and assemble.

Other objects reside in the combinations of elements, arrangements of parts, and features of construction, all as will be more fully pointed out hereinafter and disclosed in the accompanying drawings, wherein there is shown a preferred embodimentof this inventive concept.

In the drawings:

Figure 1 is a fragmentary longitudinal sectional view taken substantially along the center line of one form of arbor embodying the instant inventive concept.

AFigure 2 is a transverse sectional view taken substantially at right angles to the section shown in Figure l, or along the line 2;2 of Figure l.

FigureB is an enlarged side View partially in elevation and partially in section, showing the application of the arbor within a tube in the process of bending.

Figure 4 is a sectional view taken substantially along the line 4-4 of Figure l.

Figure 5 is an enlarged perspective view of one of the links connecting adjacent balls.

Figure 6 is a longitudinal sectional view, partially i-n elevation, through a modied form of apparatus;

Figure 7 is a continuation of Figure 6, showing the methodzof securing the rear ball to the operating shafty of the apparatus.

Figure 8 is a sectional view taken substantially along the line 8-8 of Figure 6, as viewed in the direction indicated by the arrows.'

Figure 9 is a sectional view taken substantially 4 claims. (el. 153-63) a along the line 9-9 of Figure 7, as viewed in the direction indicated by the arrows.

Similar reference characters refer to similar parts throughout the several views of the drawings.

in Figures 1 to 5, inclusive, there is generally shown at I0 a tubular rigid shank member hav-y ing a central bore II, within which is positioned a collar I2 having an extending shank I3 adapted to be secured in any desired manner to conven-V tional apparatus. The collar I2 includes a eenk trally positioned aperture or recess I4,r Within which is positioned a bifur'cated member I5, apertured to receive a pin I6, which extends transversely of thev aperture the full diameter of the bore II and is seated in the collar I2. ,The pin is adapted to pass through a suitable aperture in an extending shank I'I comprising a portion of a link generally indicated at I8, see Figure 5,r provided with bifurcations I9 having apertures therein for the accommodation of a pin 20 cor- Y outer surface of the member 23 is of circular configuration in transverse section, as indicated at 23', Figure 4. 4 y

The bifurcations I9 of the link I8 accommodate thev shank I1 of an identical link provided with a similar aperture I'I through which is passed a second pin 20 seated in interior grooves 22 of the adjacent ball 23. Successive balls 23 are secured in an identical manner for a desired length of bendable character.

As best shown in Figure 1, the lower portion of each member 23 is tapered, as at 24, in such man- 11er that when the links are positioned inside of a tube 25 having a lrelatively sharp bend, as indicated at 26, Figure 3, the lower portions 24 of the balls abut whereby the balls assume a comparative angular relation extending radially from the inner or lesser radius of the bend in the tube.

The outermost of the balls 23 contains a pin 20 passed through the bifurcations in the adjacent link I8, which outermost pin engages a tongue 21 extending from a shank 28 having a slight bend 29 therein in a direction toward the tapered portion 24 of the balls 23, and terminating in an enlarged head 30. A sliding ball member 3| of toric exterior configuration, as indicated at 32, is provided with a recessed socket 33 of a diameter to accommodate the head 30.

The Shank 28 extends into a frusto-conical recess 34 permitting relatively free bending movement of the member 3l about the shank 28 when the.

Referring now to the form of device disclosedv 3 device is inserted into a tube in the process of bending the same. The relative sliding movement of the member 3l permits the insertion of the device into,y a tube for theformation l of a bend of relatively,smallsradius, as indicatedfinFigure A modified form of construction is disclosed in Figures 6 to 9 inclusive, adapted to be utilized in, forming bends of slightly greater radius,andin cludes a plurality of balls 50, the innermost of which seats in a frusto-conical recess l-in-a tubular shank 52 provided with an annular *shoulder 53 within a bore 54. A bolt 55 vextends into the bore 54 and is provided with a nut 56- seated against the shoulder 53, the bolt 55 terminating in ,a tongue 5l adapted to .be engaged between bifurcations 58 of a link member .59, being held therein by means of a Dirl passing through suitable-.registering apertures in thetongue andV bifurcations. The link 59 extends inwardly of the adjacent ball, 55 and terminates in atongue 6 I` yengaged within the bifurcationsV 58 ofthe next lir`1k5il.y Pins 52 hold each linkand the tongue ofI theadjacent linkin related assembly andseat in annular recesses ,64 formed ,Withinl each linkin such marmer 4that the links are freely rotatable with respect to ,the flexible shaft comprised of,

sugcessivelinks 59. Thev bifurcated portions 5S of each' link are cut away `at their lower surfaces, as indicated Vat 65, in such manner as to permit relative bending of the arbor inthe same man- A ner, as indicated in connection with the Ypreviously discussed modification.

Inthis form, each of ,the fballs, llincludes a,

toroidal.. member provided with aflange ,66 Hextending to overlyingposition over thereduced periphery vof the next adjacent fball, the flange 'forrnin'g the outer extremity of asubstantially frusto-conical interior recess. (il ,terminating in the annulus .64.

Irrthis modication, the, outermost link `59 includes an extending shank; $8V `provided with a head '30 adapted to ,seatl in a recess l33 inua. toroidal member generally indicated at, 3|" and havinga Truste-conical recess 34. therein corresponding in all respects to the previously dis: ,i

cussed member 3| and serving an identical purpose.

From theforegoing,` the mode of use cf the devi-ce should now bev readily apparent. The ar V bor, in either the form shownin-Figure' 1, or thek r fovrmdisclosed in 'Figure 6, islinserted in a tube tov be bent, and pressure applied to the ends, ofthe tube to vform the bend innany desired ,conven tional manner. Obviously, in the construction inVl Figure l, the links may lassume the lposition showninFigure 3 with the bend., while in the device of Figure 6, a similar bend is permitted by'vi'rtue of the anges and theiradjacent associa-ted recesses 61.

Obviously, a relatively sharp `bend `may, ,be

formed, Aandequally obviously, the dislocation of a pin in" such manner as toinjure` the` interior of `the tubing is substantially precluded by the fact that the pin in neither modification extends entirely through the adjacent torus.

Additionally, in the modification rdisclosed in Figures 6 to'9, inclusive, relatively free rotation of thefball members 5U relative to the pinsA is permitted, thus substantially reducing the wear on any particular portion of the; apparatus and providingi an extremely durable and longlived construction.

From the foregoing itwill now` be seenythat. there isl herein providedjan 'improved device 'which' accomplishes all-the objects of this infso vention, and others, including many advantages of great practical utility and commercial impoi'tance.

Since variousembodiments maybe made of this inventive concept, and sincevarious modifications may be made in the embodiments here- Vinbefore shown anddescribed, it is to -be underof said pins extending laterally outwardly of each side of` said links,and said bore of veachballbeing formed with a pair of diametrically-opposedf longitudinally extending grooves, each rof said grooves being closed, at one end,A andr said free ends` of a pin being received in each pair off,l

grooves.

2. `A bending ballt arbor, comprisinga-plurality of balls of substantially toroidalcongura, tion, said balls each being formed with. an. axial,r

bore therethrough, a plurality .oflinks receivedin said bores, pins extending through, said `links to connect adjacent links together, the freeends.. of said pins extending laterally outwardly of.v each `side of said links,` and said boreof .each-` ball lbeing, formedwith an enlarged annular refv cess, providing with said bore aradially inwardly-lA directed annular shoulder, and thev free ends `ofr ar pinbeing seated in each recessagainst. the., shoulder thereof.

3. A .bendingball arbor,` comprisingfa pluralityyof balls ofsubstantially ytoroidal configura:

tion, said balls each being formedwith anaxial l bore therethrough, a plurality of` links received' ink said bores, pins extending throughsaid'links to conne-ct adjacent links'together, thefreeendsv of said pins extending laterally outwardly of each side of said links, and said bore of each ballbeing formedWith-recessed portions notextending tothe outer periphery of the ball and providing 4 seats for the Afree ends of one ofv saidpins;

4. A bending -ballarboncomprisingy ayplural ity of balls of substantially toroidall'cong-uration,said.balls each bei-ng formed withan ax-ial bore therethrough, a pluralityof .linksreceivedinsaidlbores, -pins extending through1said linksto connect adjacent links together, thetfree endsil ofi said `pins. extending laterally outwardly ofeach sideof said links, said-bore ofeach .ballbeings formedwith anenlargedannular recess provi;l.l

ingy withr said bore ,a radially,inwardlyedirected annular. SlilOillCler,` the i free endsy `of a pin .beinsrV seated ,in each recessvagainstthe shoulderthelee;

of, each ball having a front surface, and.said.

recess opening through said-frontfsurface to pro-l vide means for'inserting and removingpsaid-pins therefrom... l i y FRANK- CHECK, ,Sm

REFERENCES CITED.

The following references are of record ing they.

leoithis patent:`

UNITED STATES PATENTS Number Name Date.`

1,647,526` Kenney Nov. 1927 1,683,572 Mueller et al. Sept. ,4,1928- ,t 1,683,573.

Mueller et al.V Sept, L11928 

